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Bulls Tue Apr 06 2010
Tailgate Talks: David Berri of Wages of Wins
Last month in the first installment of Tailgate Talks, we featured Rick Telander, the celebrated Chicago Sun-Times sports columnist and author of the seminal Heaven Is A Playground. This month, Tailgate is talking with a nouveau member of the Fourth Estate and qualified "brain-hurting smart" economist, David Berri. Berri and his colleague Martin Schmidt maintain the popular, numbers-intensive, basketball blog, Wages Of Wins, the duo's second book, Stumbling On Wins, is out now (Tailgate will have a review of it later this week) and both of them are noted economists in the fields of sports economics and macroeconomics (where the "brain-hurting smart" comes in handy.)
Mr. Berri was generous enough to share his time and thoughts on the Chicago Bulls, their season, Derrick Rose's development and the "new stats" of sports among other things. Here is the email Q 'n A that Berri and Tailgate shared over the weekend.
The Bulls have, with fewer offensive options, a myriad of injuries to key players and worse defense, this season ended up approx. where they were last year: on the cusp of playoffs (likely fodder for CLE or ORL instead of CLE/BOS last year) vs. lottery pick (probably not nabbing Evan Turner or Cousins of Wall). Is the lower half of the East just this awful/are the Bulls this "lucky"?
The Bulls appear to be an average team. Last year the Bulls were led by Joakim Noah (8.4 Wins Produced), Ben Gordon (6.1 Wins Produced), Derrick Rose (5.3 Wins Produced), Luol Deng (4.2 Wins Produced), Kirk Hinrich (2.9 Wins Produced). This year — after 76 games — the Bulls are led by Noah (8.7 Wins Produced), Luol Deng (7.9 Wins Produced), Taj Gibson (5.9 Wins Produced), Derrick Rose (4.5 Wins Produced), and Kirk Hinrich (3.8 Wins Produced). Essentially, the Bulls lost Gordon's production and added Gibson. The net result is they are essentially where they were last season.
The problem for the Bulls is that they have a few above average players. But the team lacks a major producer of wins like LeBron James or Dwight Howard. More specifically, the Bulls don't have a single player who will produce more than 10 wins this season. Without such a player, it's very difficult for a team to become a title contender.
It seems like the lower half of the Eastern Conference has just been a game of musical chairs in recent seasons and that the Bulls along with Miami, Charlotte, Toronto, Milwaukee have been bobbing in and out depending on what shakes out in that particular season. Is this ascribed to randomness and not, you know, actual talent/capability/teams being better or worse than other teams?
This question is related to the first. Essentially each of these teams is close to average. If you look at what the veterans did last year, you would expect each of these teams to win between 35 and 45 games in 2009-10. This is indeed what's happened.
One issue we talk about in Stumbling on Wins is the Pareto Principle. This is the idea that 80% of outcomes can be tied to 20% of individuals. Although I am not sure this holds throughout the economy, it does seem to work in the NBA. About 80% of a team's wins tend to be linked to the top three players on the team. So for a team to wins 60 games, it really needs three players capable of producing 48 wins. If you look at the top three players on these teams, you simply don't see a combination capable of producing enough wins to vault these teams into title contention.
Having watched Ben Gordon for his first few seasons in Chicago, I was overjoyed that Detroit took him last offseason. You, as a Pistons fan, I suspect were/still are not using "overjoyed" to describe what Ben Gordon has done this year in MoTown. He's a black hole of possessions and I'm just curious, how do you handle a player like that on a team you are such a fan of? Also, I've got this awful feeling that Gordon will always have a job in the NBA, right?
One issue we emphasize is that scoring is overvalued in the NBA. So Ben Gordon — as long as he can score — will probably find a job in the NBA for a very long time. But it's unlikely he will ever produce many wins. Here is what Gordon has done across his career with respect to Wins Produced and Wins Produced per 48 minutes [WP48]. In looking at these numbers it's important to remember that an average player will post a WP48 of 0.100.
• 2008-09: 6.1 Wins Produced, 0.097 WP48
• 2007-08: 3.4 Wins Produced, 0.071 WP48
• 2006-07: 4.7 Wins Produced, 0.084 WP48
• 2005-06: 1.1 Wins Produced, 0.020 WP48
• 2004-05: 0.1 Wins Produced, 0.002 WP48
This season Gordon has produced -0.8 wins (after 76 games) with a -0.025 WP48.
As we note in the book, players appear to peak in performance at the age of 24 or 25. Gordon is now 26 years old, so it seems unlikely he will ever produce enough wins to justify his current contract.
As a fan... I wrote last July when the Pistons acquired Gordon and Charlie Villanueva (and failed to draft DeJuan Blair) that the Pistons were probably going to struggle this year. I certainly hoped to be wrong about the Pistons in 2009-10. Although surprises can happen in basketball, often that doesn't happen. Consequently, following the Pistons was difficult this year. That being said, it's possible for a team to win with Ben Gordon. But he's not likely to be one of these three players a team needs to be a contender.
A criticism I have of Derrick Rose this season has been his lack of offensive development (still takes a lot of long jumpers, doesn't get to the rim as frequently as he could, doesn't get to the free throw line), is this valid or is he still learning the ropes? Conversely, Joakim Noah, a relatively known quantity coming into the NBA, has quantum-leaped in terms of productivity over the course of the past two seasons. Is this unexpected or rare from a numbers/analysis? Seeing a player (not in terms of scoring necessarily) jump to the next level?
Rose is still a very young player. But if you compare him to other top point guards — at the age Rose is today — it seems possible that he will never develop into the top player people envisioned when he was taken with the first pick in 2008.
At 20 years of age (as a rookie), Chris Paul produced 17.8 wins and posted a 0.305 WP48. And Rajon Rondo — at 21 years of age — produced 9.8 wins and posted a 0.204 WP48.
Derrick Rose posted a 0.085 WP48 as a rookie (at 20 years of age) and a 0.083 WP48 this season. So he has been slightly below average as an NBA player. Again, players do seem to improve until they are 24 or 25, so Rose can certainly get better. But I am not sure he is going to ever reach what we see from Chris Paul (0.451 WP48 last year) or Rajon Rondo (0.313 WP48 last year). When you compare Rose to an average point guard he simply doesn't appear outstanding in any particular area. Consequently, Rose really doesn't produce many wins.
It's a different story when we look at Joakim Noah. Here is what Noah did across his first two seasons:
• 2007-08: 3.8 Wins Produced, 0.118 WP48
• 2008-09: 8.4 Wins Produced, 0.208 WP48
This season he has already produced 8.7 wins with a 0.245 WP48. So he has improved, although I am not sure I would call it a quantum leap. Players do tend to get better early in their careers. So I don't think what we are seeing from Noah is uncommon. It is a good sign, though, that a player who doesn't score much is being recognized by fans.
What direction do you see Chicago needing to go in for them to be able to play late into May and June in future seasons? Wade seems like a very iffy playmate for Rose, et and LeBron is really out of the question. Does Chris Bosh make the most sense, Rudy Gay? Joe Johnson? Manu? If the Bulls score no big FAs will this spring's housecleaning (bye-bye to Tyrus and Salmons) be a bust?
Let me start with where they are. The following table is what I normally offer when I analyze a team at the Wages of Wins Journal. There are two evaluations of each player. The first is what they are doing this season. The second is what we would have expected from the veterans if they maintained what they did last season.
As one can see, because of the play of Brad Miller (who is now quite old for a basketball player), the Bulls have somewhat underperformed. Even if Miller had maintained what we saw last year, though, the Bulls were not going to be serious contenders this season.
Here are some brief comments on the free agents you mentioned:
Joe Johnson and Rudy Gay are both overrated scorers. Gay has yet to be an above average player in the NBA. And while Johnson can be above average, he doesn't produce as much as his likely next contract will suggest.
Of the productive free agents noted, LeBron would obviously be the ideal choice. But LeBron is probably not coming.
Dwyane Wade would probably be the next best choice. Wade posted a 0.350 WP48 last season. Wade, though, will be 29 next year and he has a history with injuries. So he may not be worth what the Bulls would have to pay him.
On a per-minute basis, Ginobili was also very productive last season (0.335 WP48). But Ginobili is even older and also prone to injuries.
Chris Bosh is an interesting choice. His WP48 this season is 0.213. Plus he is relatively young. Bosh, though is probably not going to be enough to transform the Bulls into title contenders. The Bulls are currently getting above average production from Noah, Deng, and Gibson. But the backcourt is devoid of above average players. Adding Bosh will further strengthen the frontcourt, but the problems at guard will still persist.
Differentials, offensive/defensive efficiencies and Wins Produced are, even with the success and emergence of "Moneyball" tactics, not on the lips of the casual fan yet. Is it just a matter of time for more people/fans/teams to recognize that these numbers do matter or will it remain more of a fringe topic?
This is a difficult question to answer. Traditional economics suggests that new and better information will be adopted very quickly by people. But that doesn't seem to be what we generally see. For example, the data to calculate On-Base percentage existed in the 1860s; and Bill James was noting the value of OBP (as well as quite a bit else about baseball) back in the 1970s. Much of what James said, though, wasn't adopted by most decision-makers in baseball until the past decade. And many fans probably still don't know about OPS and other advanced stats.
The slow pace (of adaptation) we see in baseball is likely to be even slower in basketball. Even if many baseball fans are unaware of the advanced baseball stats, these same fans do know about other numbers (i.e. batting average and ERA). Basketball fans, though, tend to ignore most numbers (except scoring averages) and focus instead on artistic nature of a basketball player's performance. Given this reality, I am not optimistic that fans of the NBA are going to embrace statistics like Wins Produced very soon. Perhaps if we can get fans to look past scoring, though, we can count that as progress.
Let me close with further details on the metric of Wins Produced...
About Wins Produced: The model used to measure player performance begins with the simple notion that wins in the NBA are determined by a team's offensive and defensive efficiency. From this statistical model we can derive the value — in terms of wins — of much that is in the NBA box score. These values tell us that wins in the NBA are primarily determined by shooting efficiency and the ability of a team to capture and maintain possession of the ball. This means that an NBA player helps his team win when he is an efficient scorer, grabs rebounds, captures steals and avoids turnovers (i.e. the possession factors). Blocked shots, assists, personal fouls do matter. But shooting efficiency and the possession factors matter more.
The model explains 95% of team wins and is much more consistent across time than the plus-minus models. But it does tell us that players who score inefficiently, and/or who are below average with respect to the possession factors, do not help a team win very much. And this can be true even if the player scores more than 20 points per game. As a consequence, Wins Produced can produce results that contradict what people generally believe about NBA players. Again, popular perception is driven by scoring. So as we argue in Stumbling on Wins, perhaps what we see from Wins Produced shouldn't be that surprising.
Cam / April 23, 2010 2:48 AM
If there was any question of what a ridiculous notion this "wins produce" nonsense is, claiming Taj Gibson and Luol Deng are both better at it than Derrick Rose should put it to bed. About as relevant as the plus/minus stat.
Nobody in their right mind believes Rose is a below average player either.